Methods of reducing salmonella in poultry

ABSTRACT

Described herein are methods of reducing  Salmonella  in the intestines of poultry in need thereof by administering to a poultry bird an effective amount of an interleukin-10 peptide or an isolated antibody that specifically binds an interleukin-10 peptide. Administering may be performed within 1 to 4 weeks of harvest of the poultry in order to reduce  Salmonella  transmission to human consumers. Also included herein are finishing feeds that include an interleukin-10 peptide or an isolated antibody that specifically binds an interleukin-10 peptide.

FIELD OF THE DISCLOSURE

The present disclosure is related to methods of reducing Salmonella in the intestines of animals, including poultry.

BACKGROUND

Livestock such as poultry that are infected with pathogens, or serve as incubatory or convalescent carriers of pathogens, present problems both for the animals as well as humans who consume meat from the animals. Antibiotics are generally added to the nursery and grower feeds of poultry to promote growth and/or reduce disease occurrence during all phases of food production. The addition of antibiotics reduces the passage of pathogens such as S. Enteritidis to humans and has advantages for the health and weight of the poultry. Antibiotics promote growth through the reduction of biological stress, the decrease of bacteria, and by promoting the health of the poultry. Poultry that are healthy and disease free eat more food, and more effectively convert the food into muscle or meat. Thus, the antibiotic supplementation of poultry diet has numerous benefits.

Despite the advantages, the practice of supplementing poultry diet with antibiotics is increasingly problematic. Sub-therapeutic doses of antibiotics are linked to the increased presence of antibiotic-resistant bacterial strains in humans, animals and in the environment. It is also possible for residual antibiotics to appear in food that is meant for human consumption. To prevent residues, antibiotics are generally withdrawn from the feed of the poultry at least two weeks prior to slaughter to allow for drug clearance, and hence to prevent the antibiotics sequestered in the poultry from ingestion by humans.

Of particular importance to human consumers is Salmonellosis (Salmonella infection), associated with the pathogen Salmonella enterica subspecies enterica serovar Enteritidis (S. Enteritidis). Poultry products, including eggs and poultry birds, serve as a reservoir for S. Enteritidis. Poultry birds can be asymptomatic for Salmonella infection, thus making it difficult to isolate infected birds. The S. Enteritidis pathogen can pass to humans via contaminated poultry products through the food production chain. Undercooked or raw eggs and poultry meat thus constitute a high risk of infection for humans. In fact, poultry carcasses entering the processing environment are generally contaminated with bacteria such as Salmonella.

As one example of an attempt to prevent the transmission of Salmonella to human consumers, ground turkey samples are routinely tested for Salmonella. For example, 25 gram samples of ground turkey are tested and 50% of the samples must be free of Salmonella. Recent outbreaks of food poisoning associated with ground turkey have prompted proposals to increase the standards for ground turkey, which with current production methods may greatly increase the number of samples testing positive for Salmonella. What is needed are improved antibiotic-free methods of treating poultry to reduce the incidence of Salmonella in poultry products.

BRIEF SUMMARY

In one aspect, a method of reducing Salmonella in the intestines of poultry in need thereof comprises administering to a poultry bird an effective amount of an interleukin-10 peptide or an isolated antibody that specifically binds an interleukin-10 peptide, wherein administering is within 1 to 4 weeks of harvest of the poultry.

In another aspect, a poultry finishing feed composition comprises a basal poultry finishing feed composition, an amount of an interleukin-10 peptide or an isolated antibody that specifically binds an interleukin-10 peptide, and no added antibiotics, wherein the basal poultry finishing feed composition is suitable for feeding during the final 1 to 4 weeks prior to slaughter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the Salmonella counts vs. days post challenge at 0.341 g of antibody/kg of feed.

FIG. 2 shows the Salmonella counts vs. days post challenge at 1.705 g of antibody/kg of feed.

FIG. 3 shows the Salmonella counts vs. days post challenge at 3.41 g of antibody/kg of feed.

The above-described and other features will be appreciated and understood by those skilled in the art from the following detailed description, drawings, and appended claims.

DETAILED DESCRIPTION

Described herein are methods of reducing Salmonella in the intestines of animals, particularly poultry. Certain interleukin-10 (IL-10) peptides and anti-IL-10 peptide antibodies have been described as useful in the treatment of Coccidiosis, a protozoal infection, in animals such as poultry. The principal downside to Coccidiosis is the growth suppression and other disease effects in the birds as Coccidia is generally not transferrable to humans consuming poultry products. Because young birds are more susceptible to Coccidiosis than more mature birds, Coccidiosis is generally treated by providing anti-Coccidial agents in starter feeds. In commercial chicken production, for example, starter feeds are generally used only in the first 3 weeks of a chick's life due to the early susceptibility to Coccidiosis, the expense of feed containing additives, and concerns about carry-over of agents into produced meat. In turkeys, starter feeds may be used for 6-8 weeks after hatch. In contrast to Coccidia, infection with Salmonella bacteria often does not produce symptoms in the infected poultry, but is a serious problem when passed to humans through consumption of poultry products. An additive that can reduce Salmonella in the intestines of poultry when used in the final 1 to 4 weeks prior to harvest would greatly reduce the passage of Salmonella from poultry to humans through consumption of poultry meat. It was thus found by the present inventors that IL-10 peptides and anti-IL-10 peptide antibodies are also effective against Salmonella and represent a new strategy to prevent transmission of Salmonella to humans.

In one aspect, described herein is a method of reducing Salmonella in the intestines of poultry in need thereof comprising administering to a poultry bird an effective amount of an interleukin-10 peptide or an isolated antibody that specifically binds an interleukin-10 peptide, wherein administering is within 1 to 4 weeks of harvest of the poultry. As used herein, poultry means domesticated fowl raised for meat or eggs. In general, broiler chickens are harvested at 5 to 8 weeks after hatch, thus the interleukin-10 peptide or an isolated antibody that specifically binds an interleukin-10 peptide would be administered at weeks 3, 4, 5, 6, 7 and/or 8 after hatch. Turkeys are harvested between weeks 10-22 after hatch, thus the interleukin-10 peptide or an isolated antibody that specifically binds an interleukin-10 peptide would be administered at weeks 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 and/or 22 after hatch.

The IL-10 peptides and isolated antibodies that specifically bind to IL-10 peptides described herein reduce the Salmonella burden in chickens. Specifically, isolated antibodies that specifically bind to IL-10 peptides reduced the Salmonella burden in the ceca of chickens challenged with Salmonella enteritidis. In one aspect, the poultry to be treated is a Salmonella-tolerant bird, meaning that the bird is asymptomatic for Salmonellosis.

As used herein, the term “peptide” includes the peptide as well as pharmaceutically acceptable salts of the peptide. “Amino acid residue” means the individual amino acid units incorporated into the peptides of the disclosure. As used herein, the term “amino acid” means a naturally occurring or synthetic amino acid, as well as amino acid analogs, stereoisomers, and amino acid mimetics that function similarly to the naturally occurring amino acids.

As used herein, the term “antibody”, or “immunoglobulin”, encompasses naturally occurring antibodies, such as polyclonal and monoclonal antibodies, as well as artificial or synthetic antibodies or genetically engineered forms of antibodies, including single chain antibodies, chimeric, and bifunctional antibodies, as well as fragments thereof.

The term “isolated antibody” as used herein, refers to an antibody that is substantially free of other naturally associated molecules, or substantially free of antibodies having different antigenic specificities.

The IL-10 peptide of the present disclosure includes the amino acid sequences of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO: 8, SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID NO: 11, SEQ ID NO: 12, SEQ ID NO: 13, SEQ ID NO: 14, SEQ ID NO: 15, SEQ ID NO: 16, SEQ ID NO: 17, SEQ ID NO: 18, SEQ ID NO: 19, SEQ ID NO: 20, and combinations thereof (see Table 1). In particularly suitable embodiments, the IL-10 peptide has an amino acid sequence of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, and/or SEQ ID NO: 5.

TABLE 1 Sequence ID NO. and Corresponding Amino Acid Sequence. SEQ ID NO: AMINO ACID SEQUENCE Organism SEQ ID NO: 1 DDELNIQL Chicken, quail, turkey SEQ ID NO: 2 VLPRAMQT chicken SEQ ID NO: 3 VLPRAMKT Quail and turkey SEQ ID NO: 4 EKMDENGI Chicken, quail, turkey SEQ ID NO: 5 EPTCLHFS Chicken, quail, turkey SEQ ID NO: 6 DQMGDLL pig SEQ ID NO: 7 DQLHSLL cow SEQ ID NO: 8 VMPKAESD pig SEQ ID NO: 9 VMPQAENH Cow/sheep SEQ ID NO: 10 SKLQERGV pig SEQ ID NO: 11 SELQERGV cow SEQ ID NO: 12 ENSCIHFP pig SEQ ID NO: 13 DSSCIHLP cow SEQ ID NO: 14 DQLNSML sheep SEQ ID NO: 15 NMLQERGV sheep SEQ ID NO: 16 DSSCTHFP sheep SEQ ID NO: 17 DDLEIGL fish SEQ ID NO: 18 VLPTAIADMTEE fish SEQ ID NO: 19 TQMEGKGP fish SEQ ID NO: 20 NQCCRFV fish

SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, and/or SEQ ID NO: 5 are amino acid sequences corresponding to peptides of the IL-10 cytokine in poultry, such as chickens, quail, and turkeys. The IL-10 peptides of the present disclosure should reduce the Salmonella burden in the ceca of chickens challenged with Salmonella enteritidis by interfering with IL-10 signaling and Salmonella tolerance.

The present disclosure further includes antibodies that specifically bind to the IL-10 peptides (also referred to herein as “anti-IL-10 antibody”). These antibodies have surprisingly been found to reduce the Salmonella burden in the ceca of chickens challenged with Salmonella enteritidis when isolated and administered thereto. The antibodies of the present disclosure specifically bind to IL-10 peptides including the amino acid sequences of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO: 8, SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID NO: 11, SEQ ID NO: 12, SEQ ID NO: 13, SEQ ID NO:14, SEQ ID NO: 15, SEQ ID NO: 16, SEQ ID NO: 17, SEQ ID NO: 18, SEQ ID NO:19, SEQ ID NO: 20, and combinations thereof. In some embodiments, the isolated antibodies specifically bind to IL-10 peptides having an amino acid sequence of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, and/or SEQ ID NO: 5. In other embodiments, the isolated antibodies bind SEQ ID NO: 2, SEQ ID NO: 3, or both.

The present disclosure is further directed to generating antibodies that specifically bind to the IL-10 peptides. In one embodiment, an antibody is generated by administering the IL-10 peptides described above to an animal. Suitable animals to administer the IL-10 peptides for generating the antibodies include, for example, poultry. Exemplary poultry include chickens, turkeys, ducks, quail, and pheasant. Specific poultry include turkeys and chickens. Additional animals include livestock animals such as cows, pigs, sheep, and fish.

Exemplary methods for administering the IL-10 peptides to the animal include injection and oral administration. Injection and oral administration optionally include use of an adjuvant such as, for example, Freund's Complete adjuvant and Cholera toxin. Administration optionally further includes conjugation of the IL-10 peptide to a carrier protein such as, for example, bovine gamma globulin or keyhole limpet hemocyanin.

In one embodiment, antibodies to the IL-10 peptides are generated by an animal (referred to herein as the “producer animal”). When the animal is an avian animal, as know by those skilled in the art, the antibodies generated are passed to the egg, and may specifically be concentrated in the egg yolk of the avian producer animal. Alternatively, antibodies of the present disclosure may be isolated from the animal itself such as from serum.

In one embodiment, the antibody is an avian egg yolk antibody. Egg yolks derived from a laying hen are inexpensive, convenient and can be safer to handle as compared to the hyperimmunized mammalian sera. Also, egg yolk antibodies are able to stand up to the scrutiny under modern animal protection regulations. Immunoglobulin Y (IgY) is an avian immunoglobulin.

To produce avian egg yolk antibodies, the IL-10 peptides are injected into laying fowl, such as hens, preferably at various intervals, to induce an immune response. The hens may be injected intramuscularly or sub-cutaneously. The specific mode of injection is not essential. It is well known that the IgY antibodies produced by the hens in response to such an immune challenge are transferred and concentrated in the egg yolk.

Once the eggs are harvested, the eggs may be further processed to isolate the egg yolk, which itself may be further processed. The liquid egg yolk may be encapsulated or otherwise used in oral dosage forms. The egg yolk may be dried by spray or refractant drying methods, and the resulting dried powder may be encapsulated or otherwise used in oral dosage forms.

Alternatively, a procedure of partial purification or fractionation may be carried out to remove the majority of the non-aqueous bio-molecules and granules and optionally the majority of other proteins in the egg yolk. Exemplary purification techniques include the use of PEG, dextran sulfate or a natural gum, such as sodium alginate, carrageenan and xanthan gum, to coprecipitate the undesired substances, and the use of an aqueous buffer or water to obtain an aqueous phase rich with antibodies.

In a specific embodiment, the yolk is separated from the egg white, and then washed with distilled water to remove as much albumen as possible. The vitelline membrane encasing the yolk is punctured, and the separated yolk fraction is then diluted with an effective amount of an aqueous buffer or water to form a suspension of the egg yolk. The collected egg yolk may be diluted with an aqueous buffer solution or distilled water in a ratio of about 1:2 to about 1:40 v/v, and more specifically, in a ratio of about 1:5 to about 1:30 v/v. For efficient recovery of yolk antibodies, pH is about 5-7. Desirably, the temperature in this step is within about 0° C. to about 60° C. The suspension of the egg yolk is gently agitated to form a homogenous mixture, and then allowed to stand for a period of time sufficient to form the aqueous and non-aqueous phases. The water insoluble materials, including non-aqueous bio-molecules such as lipoproteins, phospholipids, sterols and the like, are then removed from the aqueous yolk suspension by centrifugation. The resulting antibody-containing supernatant may then be separated from the viscous precipitant by decanting, suctioning, or other like methods known in the art.

Optionally, the yolk supernatant is further treated with a high concentration of a non-denaturing salt to induce precipitation of the antibodies. Examples of the salts useful for precipitation of the yolk antibodies include, but are not limited to, NaCl, Na_(z) SO₄, (NH₄)₂SO₄, KCl, CaCl₂, and MgSO₄. Specific salts include Na₂SO₄ and (NH₄)₂SO₄. The salt concentration for precipitating antibodies depends on the type of the salt. In one embodiment, the salt is present in an amount of higher than 15% and lower than 35% by weight, specifically between 20% and 30% by weight of the salt, on the basis of the final volume of the yolk supernatant.

Alternatively, the antibodies may be purified or isolated using any conventional technique such as by immunoaffinity purification.

In one embodiment, egg yolk antibodies are prepared by the following method. Laying hens are inoculated with IL-10 peptide. Optionally, an adjuvant is administered in conjunction with the IL-10 peptide to enhance the immunization. An adjuvant useful for this purpose is a water-in-oil emulsion adjuvant such as complete Freund's adjuvant. The IL-10 peptide causes the hens to produce anti-IL-10 antibodies which are passively transferred into the egg yolk of eggs laid by the hens.

Egg yolks or whole eggs containing the anti-IL-10 antibody can be collected and homogenized to form an emulsion. The resulting emulsion can be dried to form a powder containing the anti-IL-10 antibody. This powder can then be formulated in a manner appropriate to the administration route and then administered to the desired animals using methods known in the art. The preparation is preferably administered orally, such as in an oral dosage form or in a supplement to the animal's diet.

The antibodies that specifically bind to IL-10 peptides may be isolated and purified from animal serum or egg using a suitable method known in the art. Such methods include affinity chromatography, as well as other suitable methods for antibody isolation and purification known in the art and described in U.S. Pat. No. 6,608,172 and De Meulenaer et al., “Isolation and Purification of Chicken Egg Yolk Immunoglobulins: A Review,” Food and Agricultural Immunology, Vol. 13(4), 2001, hereby incorporated by reference to the extent that they are consistent herewith. In one particularly suitable embodiment, the production animal is an avian animal such as a chicken, turkey, duck, or quail, and the antibody is isolated from the egg yolk of the egg of the avian animal.

In one embodiment, the egg yolk or serum including the antibodies are further dried to form a powder including the antibodies. The whole egg, egg yolk or parts of the egg may be spray dried. Serum may be separated from whole blood according to methods known by those skilled in the art. Spray drying of egg and serum may be performed using known spray drying methods and commercially available spray drying equipment. Dry egg and serum powders may also be prepared by lyophilization. The dried egg, egg yolk or serum powder may then be introduced into animal feeds as a feed additive to transfer antibodies to an animal.

The present disclosure is further generally directed to animal feed additives including the IL-10 peptides, or isolated antibodies which specifically bind to IL-10 peptides.

As used herein, the term “feed” broadly refers to a material, liquid or solid, that is used for nourishing an animal, and for sustaining normal or accelerated growth of an animal including newborns or young and developing animals. The term includes a compound, preparation, mixture, or composition suitable for intake by an animal. Specifically, the feed is suitable for poultry such as quail, ducks, turkeys, and chickens. A feed composition comprises a basal food composition and one or more feed additives. The term “basal food composition” refers to a food composition combinable with additives such as the peptides and antibodies described herein. Basal animal food compositions may include components such as proteins, grains, flavor compositions, vitamins, minerals, preservatives, and the like. Basal food compositions can be suitable for ingestion by a target animal. The term “feed additive” as used herein refers to components included in small quantities for the purpose of fortifying basic feed with nutrients, stimulants, medicine, or to promote feed intake or alter metabolism. Feed additives include pre-mixes of biological compositions, or in the present disclosure, pre-mixes of IL-10 peptide or isolated antibody that specifically binds to IL-10 peptide.

In one embodiment, the present disclosure includes an animal feed additive including IL-10 peptides including the amino acid sequence of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO: 8, SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID NO: 11, SEQ ID NO: 12, SEQ ID NO: 13, SEQ ID NO: 14, SEQ ID NO: 15, SEQ ID NO: 16, SEQ ID NO: 17, SEQ ID NO: 18, SEQ ID NO: 19, SEQ ID NO: 20, and combinations thereof. Particularly, the feed additive may include IL-10 peptides having an amino acid sequence of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, and/or SEQ ID NO: 5.

In another embodiment, the present disclosure includes an animal feed additive including isolated antibodies that specifically bind to the IL-10 peptide including the amino acid sequence of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO: 8, SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID NO: 11, SEQ ID NO: 12, SEQ ID NO: 13, SEQ ID NO: 14, SEQ ID NO: 15, SEQ ID NO: 16, SEQ ID NO: 17, SEQ ID NO: 18, SEQ ID NO: 19, SEQ ID NO: 20, and combinations thereof. In particularly suitable embodiments, the feed additive includes isolated antibodies that specifically bind to IL-10 peptides having the amino acid sequence of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, and/or SEQ ID NO: 5.

The IL-10 peptides or isolated antibodies which specifically bind to IL-10 peptides may be added to an animal feed as a feed additive or mixed into an animal feed by a method known in the art for mixing feed additives and animal feed. In one embodiment, the IL-10 peptide or isolated antibody which specifically binds to the IL-10 peptide is directly added to the animal feed or mixed with the animal feed just prior to feeding the animal. In another embodiment, since feeds may be pelleted or extruded, the IL-10 peptide or isolated antibody which specifically binds to the IL-10 peptide may be coated on the surface of feed (pellet) after the feed has been pelleted or extruded (post pelleted application) in order to maintain functional properties of the IL-10 peptide or isolated antibody which specifically binds to the IL-10 peptide. The addition of the IL-10 peptide or isolated antibody which specifically binds to the IL-10 peptide post pelleting can be aided by mixing the IL-10 peptide or isolated antibody which specifically binds to the IL-10 peptide in water, oil, or another suitable carrier and spraying it on the pellets as they exit the pellet die.

The amount of the IL-10 peptide or isolated antibody that specifically binds to IL-10 peptide added and/or mixed with the animal feed depends on the feeding regimen and the type of feed for the animal, and may be determined by those skilled in the art. Typically, the amounts of IL-10 peptides and/or isolated antibodies to IL-10 peptide to be used in an animal feed are summarized in Table 2 below. Antibody prepared using other sources may be calculated as equivalents using Table 2.

TABLE 2 Dose of Anti-IL-10 Antibody in Animal Feed (mg/Kg diet) prepared using egg yolk antibody. Source Low Dose High Dose Affinity purified anti-peptide 0.0015 0.5 Anti-peptide IgY 0.015 50 Dry Immune Yolk 0.8 4000 Dried Immune Whole Egg 1.5 7500

The doses shown are based on the amount of epitope specific antibody in total IgY (1 to 10%), the amount of IgY in egg (5-10 mg/Kg of feed), antibody losses due to drying storage and gastrointestinal degradation.

An animal feed may further include optional ingredients including vitamins, minerals, antibiotics, lipids, carbohydrates, proteins, antioxidants, and amino acids.

Exemplary vitamins include Vitamin A, Vitamin B, Vitamin D, Vitamin E, and Vitamin K. Exemplary minerals include calcium, phosphorus, sodium, potassium, magnesium, chlorine, cobalt, iodine, iron, manganese, copper, molybdenum, zinc and selenium. Common mineral supplements used in poultry feed, for example, include limestone, bone meal, oyster shell, sodium chloride, dicalcium phosphate, manganese sulphate, potassium iodide, and superphosphate.

In some embodiments, one or more antibiotics may be included in the animal feed along with the feed additive. Exemplary antibiotics include penicillin, streptomycin, tetracyclines, zinc bacitracin and aureomycin.

Exemplary lipids include oil seeds, oils and lipids derived from plants or animals. Sources of oilseeds, oils and lipids include corn, soybean, cotton, lupin, peanut, sunflower, canola, sesame seed oil, olive oil, copra and coconut oil, palm kernels and palm oil, casein, butterfat, lard, fish oils, linseed and oil, tuna oil, tallow and yellow grease, and mixtures thereof.

Exemplary carbohydrates include starch, cellulose, pentosans, other complex carbohydrates, corn, milo, barley, rye, oats, wheat, wheat middlings, and various grain-by-products.

Exemplary sources of protein include protein obtained from meat meal or fish meal, liquid or powdered egg, fish solubles, whey, milk protein, rice, milo, millet, corn, oats, barley, wheat, rye, wheat bran and/or middlings, soybeans, sesame seeds, peas and beans, sunflower seeds, wheat germ, alfalfa seed, flaxseed, yeast, earthworms, and fish.

Exemplary amino acids include arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine, tyrosine ethyl HCl, alanine, aspartic acid, sodium glutamate, glycine, proline, serine, cystein ethyl HCl, and analogs, and salts thereof.

Exemplary antioxidants include beta-carotene, Vitamin E, Vitamin C, and tocopherol, or synthetic antioxidants.

Specifically, the animal feed including the feed additive of either IL-10 peptide or isolated antibody is a feed for avian species such as quail, ducks, turkeys, and chickens.

In a specific embodiment, the animal feed is a finishing feed, that is, a feed composition used for poultry for consumption that is generally used in the last 1 to 4 weeks prior to slaughter to bring the poultry to market weight. Finishing feeds do not contain antibiotics and other additives that might be transferred to the meat produced upon slaughter. Finishing feeds can be distinguished from starter feeds which contain, for example, antibiotics and anti-coccidial agents which are crucial to prevent disease prior to the development of immune defenses in the young animal. Finishing feeds can also be referred to as withdraw feeds.

In one aspect, poultry finishing feed composition comprises a basal poultry finishing feed composition, an amount of an interleukin-10 peptide or an isolated antibody that specifically binds an interleukin-10 peptide, and no added antibiotics, wherein the basal poultry finishing feed composition is suitable for feeding during the final 1 to 4 weeks prior to slaughter. The interleukin-10 peptides includes SEQ IDs: 1-5. In specific embodiments, the peptide or isolated antibody is present in the poultry feed composition in an amount of 0.15 mg/kg of animal feed to 100 mg/kg of poultry feed.

The methods of the present disclosure are generally directed to methods for treating gastrointestinal Salmonella infection in an animal, or in an animal with a status of convalescence carriers of pathogen. In one embodiment, the methods involve injecting or orally administering an IL-10 peptide to an animal, thereby producing antibodies within the animal that specifically bind to the IL-10 peptide. IL-10 cytokine production is associated with down regulation of inflammation, and the IL-10 cytokine functions as an essential immunoregulator of the intestinal tract. The antibody to IL-10 peptide prevents the IL-10 cytokine from down regulating the immune system, thereby allowing the immune system to eliminate the pathogen.

In some embodiments, the methods involve injecting or orally administered an antibody to the IL-10 peptide to an animal. The term “animal”, as used herein to describe animals administered an IL-10 peptide or isolated antibody to the IL-10 peptide in accordance with the present disclosure, includes poultry such as quail, ducks, turkeys, pheasants, and chickens.

In one aspect, the present disclosure is directed to methods for preventing the transfer of human pathogens from poultry that are infected or incubatory or convalescent carriers of human pathogens to the human consumer of poultry products, or at risk of being infected or incubatory or convalescent carriers of pathogens by administering isolated antibodies that specifically bind to IL-10 peptides including the amino acid sequences selected of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO: 8, SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID NO: 11, SEQ ID NO: 12, SEQ ID NO: 13, SEQ ID NO: 14, SEQ ID NO: 15, SEQ ID NO: 16, SEQ ID NO: 17, SEQ ID NO: 18, SEQ ID NO: 19, SEQ ID NO: 20, and combinations thereof. For example, the methods may include administering isolated antibodies that specifically bind to IL-10 peptides having the amino acid sequence of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, and/or SEQ ID NO: 5. As used herein “at risk of” refers to having little resistance to a certain condition or disease (i.e., bacterial infection), including being genetically predisposed, having a family history of, and/or having symptoms of the condition or disease, or in a state of being a incubatory or convalescent carrier of pathogens and being exposed to other animals that have been exposed to or have the condition, disease or carrier status.

In an aspect, described herein is a method of reducing Salmonella in the intestines of a mammal or fish in need thereof comprising administering an effective amount of an interleukin-10 peptide or an isolated antibody that specifically binds an interleukin-10 peptide, wherein administering is within 1 to 4 weeks of harvest of the mammal or fish. When the animal is a mammal, exemplary IL-10 peptides are SEQ ID NOs: 6-16. When the animal is a fish, exemplary IL-10 peptides are SEQ ID NOs: 17-20.

The invention is further illustrated by the following non-limiting examples.

EXAMPLES Example 1 Detection of Antibody Production

In this Example, the concentration of anti-IL-10 antibody production contained within the egg yolk of IL-10 peptide-administered producer hens was determined by using Enzyme-linked immunosorbent assay (ELISA) techniques.

Specifically, each of four IL-10 peptides selected from the group consisting of IL-10 Peptide #1 (SEQ ID NO: 1), IL-10 Peptide #2 (SEQ ID NO: 2), IL-10 Peptide #3 (SEQ ID NO: 4), and IL-10 Peptide #4 (SEQ ID NO: 5) was conjugated to hen ovalbumin (OVA, Sigma, St. Louis, Mo.) for ELISA using glutaraldehyde procedure. A 96-well Nunc™ immunosorbent F-series microplate (Sigma, St. Louis, Mo.) was coated with 100 μg/plate of peptide-specific OVA conjugate in sodium carbonate coating buffer having a pH of 9.6. The plate was allowed to coat overnight (100 μl/well) at 4° C. Dry egg yolk samples containing antibody to IL-10 Peptide #1, #2, #3, or #4 were diluted 1:10 in acidic PBS having a pH of 4 and allowed to incubate overnight at 4° C. After overnight incubation, the antibody was extracted using centrifugation and used as a source of antibody to determine specificity for the peptide conjugated to the IL-10 peptide. The plate coated with OVA-peptide conjugate was washed 6 times with PBS/0.5% Tween solution, blocked with non-protein blocking buffer (200 μl/well, Pierce Scientific, Rockford, Ill.), and allowed to incubate at room temperature for at least 1 hour. The plate was washed 6 times and then samples of either adjuvant only injected control or egg antibody (isolated as described above) were added at a concentration of 100 μl/well in duplicate at 10× serial dilutions starting at 1:1000. Primary antibodies were incubated for 1 hour, the plate was washed 6 times, and then secondary antibody (HRP-conjugated goat anti-chicken antibody, Bethyl Labs, Montgomery, Tex.) was diluted in blocking buffer 1:5000 and added at a concentration of 100 μl/well. Secondary antibody was incubated for 30 minutes, the plate was washed 6 times, and then substrate solution containing 19.74 ml 0.05M sodium acetate, 100 μl 20 mg/mL 3,3′,5,5′ Tetramethyl Benzidine (TMB), 128 μl 0.5M H₂O₂ was added at a concentration of 125 μl/well and allowed to incubate until sufficient color development during the linear phase of development (blue color indicates primary antibody presence). A stop solution (0.5M sulfuric acid) was added to produce a yellow stable color and the plate was read at 450 nm on a Biotek EL800 plate reader. Duplicate optical densities were averaged and blocking buffer background was subtracted to produce a final optical density. The optical density of antibody to IL-10 peptides #1-4 and FCA control were compared to determine specificity and dose level used in the final chick experiment (see Table 3).

TABLE 3 Optical Densities of Anti-IL-10 Peptides. Dilution IL-10 #1 IL-10 #2 IL-10 #3 IL-10 #4 10 1.0585 0.935 0.968 0.8822 100 1.049 1.006 0.973 0.9 1000 0.9705 1.033 1.001 0.678 10000 0.4795 0.6775 0.593 0.224 100000 0.075 0.129 0.115 0.059 1000000 0.028 0.03 0.037 0.03 10000000 0.059 0.016 0.027 0.028 100000000 0.022 0.0055 0.0181 0.033 FCA 0.562 0.499 0.60

Example 2 Anti-IL-10 Antibody Feed Study in Chickens

This study was performed to determine whether an anti-IL-10 antibody can decrease Salmonella carrier status in poultry, specifically chickens. Chicks were challenged with Salmonella enteritidis (10⁶ per chick on day 4 or 5 post-hatch) or not challenged. This experimental protocol allows chick to become recovered carriers and thus incubatory or convalescent carriers of pathogens for humans. The antibody used was an egg yolk antibody to peptide SEQ ID NO: 2. Control antibodies were made by injecting chickens with adjuvant only (FCA antibody or isotype adjuvant control antibody). Fourteen treatments were performed:

1. normal diet, no challenge (60 chicks/pen)

2. normal diet, SE challenge (60 chicks/pen)

3. Control ab diet (0.341 g/Kg), no challenge (50 chicks/pen)

4. Control ab diet (1.705 g/Kg), no challenge (50 chicks/pen)

5. Control ab diet (3.41 g/Kg), no challenge (50 chicks/pen)

6. Control ab diet (0.341 g/Kg), SE challenge (50 chicks/pen)

7. Control ab diet (1.705 g/Kg), SE challenge (50 chicks/pen)

8. Control ab diet (0.341 g/Kg), SE challenge (50 chicks/pen)

9. IL-10 ab diet (0.341 g/Kg), no challenge (50 chicks/pen)

10. IL-10 ab diet (1.705 g/Kg), no challenge (50 chicks/pen)

11. IL-10 ab diet (3.41 g/Kg), no challenge (50 chicks/pen)

12. IL-10 ab diet (0.341 g/Kg), SE challenge (50 chicks/pen)

13. IL-10 ab diet (1.705 g/Kg), SE challenge (50 chicks/pen)

14. IL-10 ab diet (3.41 g/Kg), SE challenge (50 chicks/pen)

Chicks were placed on their respective diet immediately post-hatch. At baseline (2 days post-hatch) and each time-point (7, 11, 14, 18, 21, 30, 35 and 42 days post-hatch), five birds were sacrificed. The samples collected include: Blood, cecal content for Salmonella cfu; cecal for enrichment; tissues from ceca, liver and muscle; intestine; and cecal tonsils

FIG. 1 shows the cecal Salmonella counts vs. days post challenge at 0.341 g of antibody/kg of feed. FIG. 2 shows the cecal Salmonella counts vs. days post challenge at 1.705 g of antibody/kg of feed. FIG. 3 shows the cecal Salmonella counts vs. days post challenge at 3.41 g of antibody/kg of feed. In chicks not infected with Salmonella, Salmonella was not isolated (not shown). Shown in FIGS. 1-3 is the colony forming units (CFU) per gram of cecum contents. The first ten days post infection, there was no difference in the CFU between treatment groups. All chicks regardless of treatment had between 5 and 7 Log 10 Salmonella per gram of cecal matter. This finding showed that the anti-IL-10 antibody was not effective at preventing infection. Beginning on day 17 post-infection, the number of Salmonella per gram of cecal matter decreased, such that by day 37 the chicks not provided with either control or anti-IL-10 antibody stabilized at approximately 2 Log 10 CFU/gram cecal content, a level of bacteria that would be consistent with an incubatory or convalescent carrier status for Salmonella. The finding of no Salmonella in the ceca of control birds (n=5) at day 30 was a sampling error, since at day 37 it was clear that control chicks still had cecal Salmonella. For detecting Salmonella, a level of Salmonella of 1 Log 10 or greater is considered incubatory or convalescent carrier of Salmonella. None of the chicks fed anti-IL-10 had a carrier status by day 37. Also at day 37, 20% (1/5) of the birds not fed either control nor anti-IL-10 antibody and 20% (3/15) of chicks fed control antibody had a greater than 1 Log 10 Salmonella, whereas 0/15 of the anti-IL-10 chicks had Salmonella. Hence the use of anti-IL-10 antibodies at all doses studied eliminated an incubatory or convalescent carrier status for the chicks, where as 20% of those fed the control antibody or no antibody continued to be incubatory or convalescent carrier of Salmonella. Another objective estimate of the effects of the anti-IL-10 antibody is that the anti-IL-10 antibody reduced the amount of Salmonella in the ceca of chickens by at least 100-fold at all concentrations tested. These data suggest that the amount of antibody may be lowered from the lowest level of 0.341 g of antibody/kg of feed (0.341 g antibody/Kg of feed is equivalent to 0.7 pounds of antibody-containing yolk powder/ton of feed).

Example 3 Anti-IL-10 Antibody Feed Study in Turkeys

The USDA Food Safety and Inspection Service has decreased the tolerance for naturally abundant Salmonella species on turkey products. A study will be conducted to determine if the number of positive tests following USDA guidelines can be decreased by the use of anti-IL-10 antibody in the withdraw diet of turkeys. Turkey Toms 14-18 weeks of age are placed either on a withdraw diet with no added anti-IL-10 antibody, or a withdraw diet supplemented with 3.1 Kg IL-10 antibody in a dried egg yolk carrier per ton of feed. Turkeys are fed the two diets for two weeks, turkeys are slaughtered, and whole turkeys and their products are tested using the USDA guidelines for the present of Salmonella species. The incidence of Salmonella on turkey carcasses can be 2% in those turkeys fed a control diet, and should be lower in those turkeys fed a diet containing anti-IL-10 antibody. Ground turkey meat will also be analyzed. Control fed turkeys can have 11% or more Salmonella positive samples, while those turkeys fed a diet containing anti-IL-10 antibody should have fewer than 11% Salmonella positive samples.

The use of the terms “a” and “an” and “the” and similar referents (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms first, second etc. as used herein are not meant to denote any particular ordering, but simply for convenience to denote a plurality of, for example, layers. The terms “comprising”, “having”, “including”, and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to”) unless otherwise noted. Recitation of ranges of values are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. The endpoints of all ranges are included within the range and independently combinable. All methods described herein can be performed in a suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”), is intended merely to better illustrate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention as used herein.

While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context. 

1. A method of reducing Salmonella in the intestines of poultry in need thereof, comprising administering to a poultry bird an effective amount of an interleukin-10 peptide or an isolated antibody that specifically binds an interleukin-10 peptide, wherein administering is within 1 to 4 weeks of harvest of the poultry.
 2. The method of claim 1, wherein the poultry bird is a Salmonella incubatory or convalescent carrier.
 3. The method of claim 1, wherein the interleukin-10 peptide is SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 5, or a combination thereof.
 4. The method of claim 1, wherein the interleukin-10 peptide is SEQ ID NO: 2 or SEQ ID NO:
 3. 5. The method of claim 1, wherein the isolated antibody specifically binds SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, or SEQ ID NO:
 5. 6. The method of claim 1, wherein the isolated antibody specifically binds SEQ ID NO: 2, or SEQ ID NO:
 3. 7. The method of claim 1, wherein the poultry is a chicken, a turkey, a duck, a quail, or a pheasant.
 8. The method of claim 1, wherein the poultry is a chicken, and wherein the interleukin-10 peptide or isolated antibody that specifically binds the interleukin-10 peptide is administered at weeks 3, 4, 5, 6, 7, and/or 8 after hatch.
 9. The method of claim 1, wherein the poultry is a turkey, and wherein the interleukin-10 peptide or isolated antibody that specifically binds the interleukin-10 peptide is administered at weeks 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 and/or 22 after hatch.
 10. The method of claim 1, wherein the peptide or isolated antibody is administered by injection or oral administration.
 11. The method of claim 1, comprising administering an isolated antibody, wherein the isolated antibody is in the form of an avian egg yolk antibody.
 12. The method of claim 11, wherein the isolated antibody specifically binds SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, or SEQ ID NO:
 5. 13. The method of claim 11, wherein the isolated antibody specifically binds SEQ ID NO: 2, or SEQ ID NO:
 3. 14. The method of claim 1, wherein the peptide or isolated antibody is administered in the form of a poultry feed composition.
 15. The method of claim 14, wherein the poultry feed composition is a finishing feed comprising no added antibiotics.
 16. The method of claim 14, wherein the peptide or isolated antibody is present in the poultry feed composition in an amount of 0.15 mg/kg of animal feed to 100 mg/kg of poultry feed.
 17. A poultry finishing feed composition comprising a basal poultry finishing feed composition, an amount of an interleukin-10 peptide or an isolated antibody that specifically binds an interleukin-10 peptide, and no added antibiotics, wherein the basal poultry finishing feed composition is suitable for feeding during the final 1 to 4 weeks prior to slaughter.
 18. The poultry feed finishing composition of claim 17, wherein the isolated antibody is in the form of an egg yolk antibody.
 19. The poultry feed finishing composition of claim 18, wherein the isolated antibody specifically binds SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, or SEQ ID NO:
 5. 20. The poultry feed finishing composition of claim 18, wherein the isolated antibody specifically binds SEQ ID NO: 2, or SEQ ID NO:
 3. 21. The poultry feed finishing composition of claim 17, wherein an interleukin-10 peptide is SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 5, or a combination thereof.
 22. The poultry feed finishing composition of claim 17, wherein an interleukin-10 peptide is SEQ ID NO: 2, SEQ ID NO: 3, or a combination thereof. 